1. Field of the Invention
The invention relates generally to a device for welding thin metal sheets and, more particularly, to a stationary, water-cooled welding device for welding the lengthwise edges of a metal band formed into a tube, under protective gas, with the aid of one or more non-fusing electrodes located in the welding device. Each electrode is held by an electrode clamp in a burner housing and the electrode clamp is held in the burner housing by a clamp holder.
2. Description of the Prior Art
A device for welding is known from U.S. Pat. No. 3,931,489. The known device contains a fixed burner head with three electrodes, each located in an electrode holder. The tube to be welded passes under the burner head and an arc is produced between each electrode and the tube. A cloud of protective gas flows around the arc and the welding area. The production process must be interrupted when an electrode is used up. The burner head swings out of the welding plane and, after the electrode clamps have been loosened by means of locking screws, the electrodes can be pulled downwards out of the electrode clamps and replaced by new electrodes. If the device is being used to weld a metal tube in conjunction with a device that produces plastic tubes, i.e., in an installation for producing compound metal/plastic tubes, the changing of the electrodes must take place in the shortest time.